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The ' eductor-jet pump' link just sends you back to this page. What the cabbage? — Preceding unsigned comment added by 69.171.96.6 ( talk) 15:12, 28 January 2013 (UTC)
Moved to article. -- Dore chakravarty 05:04, 5 December 2005 (UTC)
In the second paragraph the word "atmosphere" links to a disambiguation page, what does it mean in this context? Bergsten 21:28, 6 December 2005 (UTC)
I suggest that Injector and Steam injector be merged. Biscuittin ( talk) 09:45, 9 December 2007 (UTC)
I'm of the view we should try and separate injector and ejector. The two contrivances carry out two totally different jobs. The only link between the two is utilisation of the Bernoulli effect. 7severn7 ( talk) 21:59, 24 January 2010 (UTC)
(unindent)Andy, did you not note that I carefully said (above) that "...they are essentially all one and the same device"? I did not say they were identical. Have you forgotten that you admitted they "... might use the same principle" ?? Are you deliberately being obtuse when you say that you don't understand the corollary with heat exchangers, compressors, pumps and autos? Each of those words encompasses various types of the same basic principle ... heat exchange, compression of a gas, pumping of a liquid and automotive power. Wikipedia has one article covering all types of heat exchange, one article covering all types of compressors, one article covering all types of pumps ... even though the various singular types within each category may serve different uses and are not identical with each other. So why are you so fixated on the point that they are not identical in every aspect?
By the way, all injectors do not use steam ... there are many other fluids used as their motive fluid. The same holds true for ejectors, eductors, aspirators, etc., etc.
It is your type of attitude that eventually drives people away from Wikipedia. mbeychok ( talk) 01:26, 27 February 2012 (UTC)
Andy has neatly identified the difference with his example from locomotives: there are two completely separate functions with very different methods of operation. The topic is sufficiently distinct from general engineering to warrant specialised articles. The merger was totally misconceived and should be reverted.-- Old Moonraker ( talk) 12:25, 27 February 2012 (UTC)
Do you think this article would benefit from more stuff on downstream equipment from these ejectors? Not sure if this to much information for an article such as this. These systems are notoriously difficult to operate and design. However, these issues probably do not apply in all areas of ejector appplication. Toothtools ( talk) 21:38, 27 June 2008 (UTC)
Such "steam injectors" take advantage of the latent heat released by the resulting condensation of the motive steam.
In which way does the steam injector take advantage of the latent heat? The latent heat will pre-heat the water before injection, but the same principle should also work with a fluid that has no latent heat. What is needed is a change in density by condensation. -- Hokanomono ✉ 08:24, 11 June 2014 (UTC)
copied from User talk:Andy Dingley:
end of copied section
I understand that condensation is nescessary. Work is pressure × volume, therefore steam (large volume) can easily pump in water (small volume). Of course you need to invest the latent heat in the boiler in order to get steam and drive the rankine cycle, but I think it is misleading to say that the latent heat released would be the source of the excess energy. The energy balance would be fine in an open cycle, too. At atmospheric pressure the change of volume is responsible for only 8% of the latent heat of vaporization. -- Hokanomono ✉ 20:51, 19 June 2014 (UTC)
The photo of the Nathan 4000 Non-lifting injector at the top of this article is pretty useless. It's unclear what part of the photo is actually an injector. Has anybody got a better one? -- Roly ( talk) 19:01, 28 November 2014 (UTC)
On the assumption that there's nothing particularly special about the Nathan 4000; how about this generic Steam Injector photo?
-- Roly ( talk) 19:13, 28 November 2014 (UTC)
Before immediately just jumping into how they work, it would be good to explain the point of the device. *Why* are they used? e.g. instead of other types of pump? What is the result that's being sought?
The description says "...creates a low pressure zone that draws in and entrains a suction fluid. After passing through the throat of the injector, the mixed fluid expands and the velocity is reduced which results in recompressing..."
Which sort of hints that the purpose of the device is also for "mixing" fluids, but it sounds like it went through low pressure, and then "recompressed"... why "do and undo"? what is the end result? What has changed? Is the mixed fluid then also diffused (with some of the remaining added kinetic energy, perhaps to keep it mixed with even more air to not recondense?) Please explain.
There is too much "what's going on" and not enough "what's the point" in the introduction.
Is it "just a pump", or is it something more? (There's not much about "Injectors" in the general article on "pump"s.)
(The "Modern uses" section is just a list, but it doesn't explain how this device manages to satisfy these particular needs any differently/better than some other choice of pump... it just somehow does.)
When should one consider using an injector in a design for something that needs a pump? 104.5.72.176 ( talk) 16:09, 26 July 2015 (UTC)
Recent edits removed:
"The addition of heat to the flow of water lessens the effect of the injected water in cooling the water in the boiler compared to the case of cold water injected via a mechanical feed pump."
describing this as redundant, and the following comparison to a feed pump was dismissed with "no need to compare to a pump". I do not feel it is remotely redundant; feed pumps were (as is discussed in the article) widely used on locomotives before the invention of the injector and the injector's superiority to them (thermal efficiency, limited number of moving parts, and ease of adjustment of the water input) is entirely germane to this article. I invite comments from other editors. Pinkbeast ( talk) 23:16, 31 October 2016 (UTC)
It would be very could if this article had more information on the theory of injectors and (easily applicable) formulas for dimensioning (theoretical formulas, and practical "cookbook" formulas taking various non-ideal inefficiencies into account). It may be good to divide this into four different regimes (in fact the articles should be generalized linking to or treating the steam injector a special case), gas-gas, gas-liquid, liquid-gas and liquid-liquid injectors (steam being gas of course). 150.227.15.253 ( talk) 11:19, 28 January 2019 (UTC)
I found this article hard to understand and confusing. Now I know why. The article was the result of a merger that was never cleaned up. Without explaining how a simple jet pump works, the article starts with something much more complicated, and the simple version only comes later. The water injector for a steam engine is a very specialized jet pump, and the article should tell how it builds upon a simple jet pump. Comfr ( talk) 18:50, 25 October 2020 (UTC)
A discussion is taking place to address the redirect
Eductor-jet pump. The discussion will occur at
Wikipedia:Redirects for discussion/Log/2021 March 31#Eductor-jet pump until a consensus is reached, and readers of this page are welcome to contribute to the discussion.
Cnilep (
talk)
06:44, 31 March 2021 (UTC)
![]() | This article is rated C-class on Wikipedia's
content assessment scale. It is of interest to the following WikiProjects: | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
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The ' eductor-jet pump' link just sends you back to this page. What the cabbage? — Preceding unsigned comment added by 69.171.96.6 ( talk) 15:12, 28 January 2013 (UTC)
Moved to article. -- Dore chakravarty 05:04, 5 December 2005 (UTC)
In the second paragraph the word "atmosphere" links to a disambiguation page, what does it mean in this context? Bergsten 21:28, 6 December 2005 (UTC)
I suggest that Injector and Steam injector be merged. Biscuittin ( talk) 09:45, 9 December 2007 (UTC)
I'm of the view we should try and separate injector and ejector. The two contrivances carry out two totally different jobs. The only link between the two is utilisation of the Bernoulli effect. 7severn7 ( talk) 21:59, 24 January 2010 (UTC)
(unindent)Andy, did you not note that I carefully said (above) that "...they are essentially all one and the same device"? I did not say they were identical. Have you forgotten that you admitted they "... might use the same principle" ?? Are you deliberately being obtuse when you say that you don't understand the corollary with heat exchangers, compressors, pumps and autos? Each of those words encompasses various types of the same basic principle ... heat exchange, compression of a gas, pumping of a liquid and automotive power. Wikipedia has one article covering all types of heat exchange, one article covering all types of compressors, one article covering all types of pumps ... even though the various singular types within each category may serve different uses and are not identical with each other. So why are you so fixated on the point that they are not identical in every aspect?
By the way, all injectors do not use steam ... there are many other fluids used as their motive fluid. The same holds true for ejectors, eductors, aspirators, etc., etc.
It is your type of attitude that eventually drives people away from Wikipedia. mbeychok ( talk) 01:26, 27 February 2012 (UTC)
Andy has neatly identified the difference with his example from locomotives: there are two completely separate functions with very different methods of operation. The topic is sufficiently distinct from general engineering to warrant specialised articles. The merger was totally misconceived and should be reverted.-- Old Moonraker ( talk) 12:25, 27 February 2012 (UTC)
Do you think this article would benefit from more stuff on downstream equipment from these ejectors? Not sure if this to much information for an article such as this. These systems are notoriously difficult to operate and design. However, these issues probably do not apply in all areas of ejector appplication. Toothtools ( talk) 21:38, 27 June 2008 (UTC)
Such "steam injectors" take advantage of the latent heat released by the resulting condensation of the motive steam.
In which way does the steam injector take advantage of the latent heat? The latent heat will pre-heat the water before injection, but the same principle should also work with a fluid that has no latent heat. What is needed is a change in density by condensation. -- Hokanomono ✉ 08:24, 11 June 2014 (UTC)
copied from User talk:Andy Dingley:
end of copied section
I understand that condensation is nescessary. Work is pressure × volume, therefore steam (large volume) can easily pump in water (small volume). Of course you need to invest the latent heat in the boiler in order to get steam and drive the rankine cycle, but I think it is misleading to say that the latent heat released would be the source of the excess energy. The energy balance would be fine in an open cycle, too. At atmospheric pressure the change of volume is responsible for only 8% of the latent heat of vaporization. -- Hokanomono ✉ 20:51, 19 June 2014 (UTC)
The photo of the Nathan 4000 Non-lifting injector at the top of this article is pretty useless. It's unclear what part of the photo is actually an injector. Has anybody got a better one? -- Roly ( talk) 19:01, 28 November 2014 (UTC)
On the assumption that there's nothing particularly special about the Nathan 4000; how about this generic Steam Injector photo?
-- Roly ( talk) 19:13, 28 November 2014 (UTC)
Before immediately just jumping into how they work, it would be good to explain the point of the device. *Why* are they used? e.g. instead of other types of pump? What is the result that's being sought?
The description says "...creates a low pressure zone that draws in and entrains a suction fluid. After passing through the throat of the injector, the mixed fluid expands and the velocity is reduced which results in recompressing..."
Which sort of hints that the purpose of the device is also for "mixing" fluids, but it sounds like it went through low pressure, and then "recompressed"... why "do and undo"? what is the end result? What has changed? Is the mixed fluid then also diffused (with some of the remaining added kinetic energy, perhaps to keep it mixed with even more air to not recondense?) Please explain.
There is too much "what's going on" and not enough "what's the point" in the introduction.
Is it "just a pump", or is it something more? (There's not much about "Injectors" in the general article on "pump"s.)
(The "Modern uses" section is just a list, but it doesn't explain how this device manages to satisfy these particular needs any differently/better than some other choice of pump... it just somehow does.)
When should one consider using an injector in a design for something that needs a pump? 104.5.72.176 ( talk) 16:09, 26 July 2015 (UTC)
Recent edits removed:
"The addition of heat to the flow of water lessens the effect of the injected water in cooling the water in the boiler compared to the case of cold water injected via a mechanical feed pump."
describing this as redundant, and the following comparison to a feed pump was dismissed with "no need to compare to a pump". I do not feel it is remotely redundant; feed pumps were (as is discussed in the article) widely used on locomotives before the invention of the injector and the injector's superiority to them (thermal efficiency, limited number of moving parts, and ease of adjustment of the water input) is entirely germane to this article. I invite comments from other editors. Pinkbeast ( talk) 23:16, 31 October 2016 (UTC)
It would be very could if this article had more information on the theory of injectors and (easily applicable) formulas for dimensioning (theoretical formulas, and practical "cookbook" formulas taking various non-ideal inefficiencies into account). It may be good to divide this into four different regimes (in fact the articles should be generalized linking to or treating the steam injector a special case), gas-gas, gas-liquid, liquid-gas and liquid-liquid injectors (steam being gas of course). 150.227.15.253 ( talk) 11:19, 28 January 2019 (UTC)
I found this article hard to understand and confusing. Now I know why. The article was the result of a merger that was never cleaned up. Without explaining how a simple jet pump works, the article starts with something much more complicated, and the simple version only comes later. The water injector for a steam engine is a very specialized jet pump, and the article should tell how it builds upon a simple jet pump. Comfr ( talk) 18:50, 25 October 2020 (UTC)
A discussion is taking place to address the redirect
Eductor-jet pump. The discussion will occur at
Wikipedia:Redirects for discussion/Log/2021 March 31#Eductor-jet pump until a consensus is reached, and readers of this page are welcome to contribute to the discussion.
Cnilep (
talk)
06:44, 31 March 2021 (UTC)